sage: SG4=SymmetricGroupAlgebra(ZZ,4)sage: SG4(1).is_central()Truesage: SG4(Permutation([1,3,2,4])).is_central()Falsesage: A=GroupAlgebras(QQ).example();AAlgebra of Dihedral group of order 8 as a permutation group over Rational Fieldsage: sum(iforiinA.basis()).is_central()True